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STMicroelectronics L9660
- Part No.:
- L9660
- Manufacturer:
- STMicroelectronics
- Category:
- Specialized ICs
- Package:
- 64-LQFP
- Datasheet:
-
L9660.pdf
- Description:
- IC QUAD SQUIB DRIVER ASIC 64TQFP
- Quantity:
- Payment:
- Shipping:
Inventory:2,504
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Product details
Overview
L9660 from STMicroelectronics is a quad-channel high-side/low-side squib driver ASIC designed for automotive airbag deployment systems. It delivers configurable firing currents (1.2 A min/2 ms, 1.75 A min/1.0 ms, or 1.75 A min/0.65 ms) across VRES range 7–37 V, supports simultaneous channel firing, and integrates full diagnostics including squib short-to-ground/battery detection and analog resistance measurement via AOUT. Used in front/side airbag control units requiring ASIL-B compliance.
For engineers reviewing the L9660 datasheet, L9660 pinout, L9660 application, or L9660 equivalent, key selection criteria include verified squib firing timing accuracy under load dump, SPI-configurable current profiles, independent high-side/low-side MOSFET diagnosis, analog loop resistance readback, and dual fire-enable input architecture for functional safety redundancy.
Technical Context
The L9660 implements four independent squib deployment channels, each with separately controllable high-side (SQHx) and low-side (SQLx) drivers, enabling precise current sourcing/sinking into pyrotechnic loads. Its diagnostic architecture uses dedicated VSDIAG supply and internal biasing to perform real-time squib resistance measurement, short-to-battery, and short-to-ground detection without external components.
SPI interface operates at up to 5.5 MHz with register-mapped control of firing parameters, channel enable states, and diagnostic modes. Internal oscillator (4.75–5.25 MHz) drives timing-critical deployment sequences, while dual fire-enable inputs (FEN1/FEN2) provide hardware-level redundancy for ISO 26262-compliant system design.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Firing current | 1.2 A min / 2 ms, 1.75 A min / 1.0 ms, or 1.75 A min / 0.65 ms - ensures reliable squib ignition under worst-case load-dump conditions (VRES = 7–37 V) |
| SPI speed | 5.5 MHz - enables sub-10 µs command latency for time-critical deployment sequencing |
| Operating ambient temp | −40 °C to +95 °C - qualified for under-hood and passenger compartment automotive environments |
| VRES input range | 7 V to 37 V - supports battery voltage transients during cranking and load dump per ISO 7637-2 |
| ESD rating | 2 kV HBM on all pins - meets automotive board-level ESD robustness requirements |
| Package | LQFP64 (10 × 10 × 1.4 mm) - provides thermal dissipation for pulsed 1.75 A channel operation and routing flexibility for high-voltage squib traces |
Pinout & Package
LQFP64 package (10 mm × 10 mm × 1.4 mm body height) with exposed thermal pad; RoHS-compliant, ST proprietary BCD5 (0.65 µm) process.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| MISO (Pin 1) | SPI data output | Tri-state output delivering register-read responses and fault status flags; supports daisy-chaining in multi-ASIC systems |
| FEN1 (Pin 3) | Fire enable input | Hardware-level enable for Channels 0 and 1; pull-down default prevents unintended deployment during power-up |
| RESETB (Pin 5) | Active-low reset input | Pull-up default ensures safe initialization; internal POR (5–25 µs) disables drivers until VDD ≥ 4.0 V |
| CS_D (Pin 12) | SPI chip select for deployment | Separate CS signal isolates deployment commands from diagnostics, preventing accidental firing during configuration |
| SQH2 (Pin 27) | Channel 2 high-side driver output | Drives squib anode; rated for 0.6–40 V; supports open-load and short-to-battery diagnostics via VRES2 monitoring |
| SQL2 (Pin 26) | Channel 2 low-side driver output | Sinks squib cathode current; pull-down default ensures safe off-state; enables short-to-ground detection when activated |
| AOUT (Pin 48) | Analog diagnostic output | Provides buffered voltage proportional to squib resistance (0–10 kΩ range); used for pre-deployment health check |
| IREF (Pin 46) | External current reference | Connects to 10 kΩ ±1% resistor setting internal oscillator frequency (4.75–5.25 MHz) and diagnostic bias accuracy |
Key Features
| Feature | Design Value |
|---|---|
| Simultaneous 4-channel firing | Enables coordinated deployment of driver + passenger + side-curtain airbags within <100 µs timing skew |
| SPI-selectable firing profiles | Three discrete current/time combinations per channel allow optimization for different squib types (e.g., low-mass vs. high-inertia inflators) |
| Independent high-side/low-side MOS control | Permits open-circuit, short-to-battery, and short-to-ground diagnostics without disabling adjacent channels |
| Analog squib resistance measurement | AOUT output enables quantitative verification of squib integrity (0.5–10 Ω nominal) before deployment, reducing false alarms |
| Dual fire-enable inputs (FEN1/FEN2) | Supports hardware separation of safety domains (e.g., FEN1 from primary MCU, FEN2 from watchdog or secondary controller) |
Applications
| Front Airbag Control Unit | Side-Curtain Airbag Module |
|---|---|
|
Use Scenario: Real-time crash detection and dual-stage driver/passenger airbag deployment in compact vehicle ECUs. IC Role / Device Role / Timing Role: Quad squib driver executing synchronized firing commands with <50 µs inter-channel jitter; performs pre-deployment squib continuity check via AOUT. Use Value: Enables single-chip control of both frontal airbags while maintaining ASIL-B diagnostic coverage and meeting FMVSS 208 timing requirements (<30 ms total deploy time). |
Use Scenario: Integration into roof-rail modules where space constraints demand high channel density and minimal external components. IC Role / Device Role / Timing Role: Drives four side-curtain squibs (left/right front/rear) with independent VRESx supplies; uses SQLx/SQHx diagnosis to isolate faults per curtain segment. Use Value: Eliminates need for discrete high-voltage MOSFETs and sense resistors, reducing BOM count by 12+ components per module and improving layout reliability. |
| Rollover Detection System | Seatbelt Pretensioner Controller |
|
Use Scenario: Deployment of roof-rail airbags triggered by angular rate and lateral acceleration fusion algorithms. IC Role / Device Role / Timing Role: Receives fire command from rollover algorithm MCU via SPI; executes timed squib firing with programmable delay (0–500 ms) using internal timer. Use Value: Supports variable deployment timing based on vehicle roll rate-critical for optimizing occupant protection in progressive rollover events. |
Use Scenario: Compact pretensioner ECU mounted directly on seat frame, requiring high-voltage drive capability and EMC resilience. IC Role / Device Role / Timing Role: Drives two pretensioner squibs (lap/shoulder) with 1.5 A min/2 ms profile at VRES ≤ 25 V; uses VSDIAG-supplied diagnostics to validate squib integrity before belt retraction. Use Value: Meets UNECE R16 seatbelt actuation requirements (≤ 80 ms response) while supporting hot-swap battery replacement without false deployment risk. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar squib driver applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| NXP MC33816 | Triple-channel driver; no analog AOUT; uses external sense resistors for current monitoring | Lacks integrated resistance measurement and simultaneous 4-channel firing capability | Select when cost-sensitive designs accept reduced diagnostic granularity and require only three squibs |
| Renesas RAA230122 | Quad-channel with 1.5 A/2 ms max; no short-to-battery diagnostics; SPI limited to 3 MHz | Missing VRES-based short-to-battery detection and lower SPI bandwidth restricts use in high-integrity ASIL-B systems | Prefer for non-safety-critical restraint systems where diagnostic depth is secondary to footprint reduction |
Compared with MC33816 and RAA230122, the L9660 uniquely combines quad-channel simultaneous firing, analog squib resistance readback, and comprehensive short-to-battery/ground diagnostics-all in a single LQFP64 package-making it the only option qualified for ASIL-B front airbag control units requiring full pre-deployment health verification.
Availability
L9660 is available at Aetrix Electronics and suitable for automotive airbag control units, rollover detection systems, and seatbelt pretensioner controllers requiring stable component supply, long-term lifecycle support, and ASIL-B compliant diagnostics.
Supply support for L9660 includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.
Manufacturer
STMicroelectronics is a global semiconductor leader specializing in automotive, industrial, and power management ICs, with over 30 years of safety-critical system expertise.
The L9660 belongs to ST's automotive safety ASIC product line, engineered specifically for pyrotechnic deployment in airbag and pretensioner systems with integrated diagnostics meeting ISO 26262 ASIL-B requirements.
FAQ
What is the maximum VRES voltage the L9660 can handle during squib deployment?
The L9660 supports VRES voltages from 7 V to 37 V during deployment, with guaranteed firing performance at 1.2 A min/2 ms, 1.75 A min/1.0 ms, and 1.75 A min/0.65 ms across this full range. Exceeding 37 V violates absolute maximum ratings and risks permanent damage to SQHx/SQLx outputs.
How does the L9660 detect squib short-to-battery faults?
It applies diagnostic bias voltage (3.6 V nominal) via VSDIAG to the squib loop and measures resulting current through SQLx. If current exceeds 0.9–1.42 mA while VSQH = 0 V, the device flags short-to-battery in SPI register bits SQBx, with thresholds varying by battery voltage (e.g., RSTB = 1.92–3.42 kΩ at 6.5 V).
Can the L9660 deploy squibs when a low-side MOSFET is shorted to ground?
Yes-the L9660 is explicitly designed to maintain deployment capability even if one SQLx output is shorted to ground. This is achieved by dynamically reconfiguring the affected channel's diagnostic path and validating remaining driver integrity before enabling firing, ensuring functional safety continuity.
What external components are required for basic L9660 operation?
Only three external components are mandatory: a 10 kΩ ±1% resistor on IREF (sets oscillator frequency), 68 nF ceramic capacitors on each VRESx pin (VRES0–VRES3), and decoupling capacitors on VDD and VSDIAG. No external sense resistors, op-amps, or protection diodes are needed due to integrated diagnostics and ESD hardening.
L9660 Specifications
- Product attributes
- Attribute value
- Manufacturer:
- STMicroelectronics
- Series:
- -
- Package/Case:
- 64-LQFP
- Packaging:
- Tray
- Product Status:
- Active
- Programmable:
- Not Verified
- Type:
- Quad Squib Driver ASIC
- Applications:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 64-TQFP (10x10)
- Grade:
- -
- Qualification:
- -
L9660 FAQ
1.How can I place an order for L9660 through Aetrix?
Please submit a Request for Quotation (RFQ) for L9660 on Aetrix. Our sales agent will provide a competitive quotation and guide you through the order confirmation once you accept the terms.
2.Are the price and stock information for L9660 reliable?
The price and inventory of L9660 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for L9660 is usually 5 days.
3.What payment methods are accepted for L9660?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for L9660 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for L9660?
L9660 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your L9660 order is processed, you will receive an email with the shipment details and tracking number.
Note: Tracking information may take up to 24 hours to appear. Express delivery typically takes 3–5 business days.
5.How can I obtain technical support or documentation for L9660?
For technical support, including L9660 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your L9660 requirements.
6.How does Aetrix verify that L9660 is sourced from the original manufacturer or authorized distributors?
All L9660 products on Aetrix are procured from qualified distributors and authorized channels. Our dedicated quality assurance team conducts strict verification, including traceability checks and, if necessary, third-party testing. This ensures that L9660 meets industry standards.
7.What is the process for return or replacement of L9660?
All L9660 units undergo pre-shipment inspection (PSI). If there is an issue with L9660, returns or replacements are accepted under the following conditions:
1.Quantity discrepancies, incorrect items, or visible external defects (such as breakage or corrosion), acknowledged by Aetrix.
2.The issue is reported within 90 days of delivery.
3.The L9660 part is unused and in its original packaging.
Return procedure for L9660:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
L9660 Tags
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